Abstract: Interfacial friction effects between specimens and bars in SHPB technique were studied. Five materials with different features,silicon rubber, polyurethane foam, Comp.B explosive, PBX-HMX(97%) polymer bonded explosive and 6061-T6 aluminum alloy,were chosed as specimens. Experimental results show that interfacial friction effects in SHPB tests are related with the tested material properties. Based on the isotropic elastic hypothesis, a theoretic analysis is made on an energy conservation consideration. The reduced theoretic formulations show that material Poisson's ratio, interfacial friction coefficient, length-to-diameter ratio of the specimens and axial strains are four influent factors for the friction effects.